**9. Secretory IgA and intestinal DCs**

Total serum protein in goats is in the range 6.75–7.53 g/dL [112, 113]. In the group of proteins, fibrinogen levels in goats fall between 0.1 and 0.4 g/dL, which are less compared to cows. In some instances hyperfibrinogenemia occurs with neutrophilia after inflammatory responses. In goats, however, maximum plasma fibrinogen levels are 1.1 g/dL during inflammation [114]. In the protein gamma globulins share considerably. In goat, there are three main immunoglobulins; Ig G, Ig A, and Ig M. In caprine, like in cattle and sheep, there are further two distinct IgG subclasses, IgG1 and IgG2 [115]. At the birth, IgG1 is present in the colostrum. Moreover, IgG2 is preferentially transported to mammary glands from serum as IgG1 share high affinity to IgG1 for Fc receptors on mammary epithelial cells [116]. The goat IgG1 is the subclass that is predominant circulating antibody

**Figure 9.** *miRNA regulation of immune response against Helminth infection.*

which is produced in response to any infection which later isotopically switch to Ig E functions [117]. Locally generated IgG1 is also detected after arthritis encephalitis (CAE) virus infection in the synovial fluid [118]. Very few work has been done for caprine IgM concentrations and activities. All the ruminant species observe little structural and functional differences [119]. Caprine IgA, on the other hand, is detectable from serum, colostrum, milk, saliva, and urine. IgA is the primary immunoglobulin present in mucosal surfaces. The secretory element to IgA could be found in either free-state or bound to IgA molecule. The serum very small amount of IgA is linked to secretory component [120]. Goat mucosal immune system produces sIgA by antibody producing cells differentiated from activated B cells. Immunoglobulin class switch do occur from IgA in gut-associated lymphoid (GAL) in Peyer's patches, MLNs, and ILFs within the lamina propria [28, 121]. The humoral immunoglobulin isotype switch occurs through intestinal pDCs, T cell-independent manner and B cell-activating factors (BAFFs) and A proliferation-inducing ligand (APRIL) proliferation inducing ligand [73]. Like in all ruminants, including goats, IgE typically associated to its biologic activities. Today IgE is accepted as useful marker in identifying different phases of parasites and parasite resistance. Nucleic acid sequencing in caprine IgE DNA is part of the overall effort [110, 122]. Goat's complement system is provided with limited concentrations [123]. Dynamic studies showed that in less than 6 month old young and adult indicate significant hemolytic, conglutinating, and bactericidal complement activities [124] (**Figure 9**).
